SIGNIFICANCE OF THE ELECTROMAGNETIC FORCES ON THE MECHANICAL RESONANCES OF STATOR LAMINATIONS

✍ Scribed by C. Öztürk; A. Bahadir

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 309 KB
• Volume: 10
• Category: Article
• ISSN: 0888-3270
• DOI: 10.1006/mssp.1996.0035

✦ Synopsis

The laminated structure of the stator core of fractional horsepower electric motors consists of plates of ferromagnetic materials that can have unusually large deformation coefficients when an electric field is applied. The influence of the compressive stresses is the cause of significant changes in the harmonics that can be explained by the effect of the stress on the harmonic content of the flux density waveform. Magnetostriction harmonics are important when considering the significant contribution to audible noise of electric motors. The significance of magnetostrictive forces increases when they excite the lamination plates around their mechanical resonances. The combined effects of the radial components of the electromagnetic forces and the magnetostrictive deformation can cause further problems of amplification of noise by setting the core and frame in motion. This study investigates the effects of magnetostrictive forces on the laminated mechanical structure of the stator core by referring to changes of the plate materials depending upon the heat treatments, magnetic properties, and the percentage of silicon alloying that were all considered as factors which modify the effects of magnetostriction.